1. Field of the Invention
The present invention relates to a nut feeding system for feeding a nut to a predetermined feeding position.
2. Description of the Related Art
For example, a tire is attached to an axle by screwing a nut to a bolt provided at a hub of a vehicle at a tire attachment station in a manufacturing line of vehicles. The screw operation of the nut at the station is conducted by using a nut runner. Since one of the axis direction of the nut used here is defined as a predetermined fastening direction, it is necessary to set the nut to the nut runner aligned in the correct fastening direction.
There has been known a feeding apparatus of a nut for feeding the nut towards the proper fastening direction so as to smoothly conduct a setting operation of the nut to the nut runner (refer to Japanese Utility Model Laid-Open Publication No. H02-34516). This apparatus comprises a chute for aligning the orientation of axes directions of a plurality of nuts and feeding them, an alignment ring having a nut supply hole in an outer periphery which communicates with a terminal end portion of the chute to accommodate the nut, and a pushrod for pushing out the nut in the nut supply hole to the feeding direction along the axis line direction of the nut.
Then, the nut is pushed out from the nut supply hole by the pushrod after changing the posture of the nut by rotating the alignment ring so that the orientation of the axis line of the nut accommodated in the nut supply hole is directed to the predetermined fastening direction. By doing so, the nut can be supplied towards the appropriate fastening direction.
However, it is likely that the above conventional art is not able to perform smooth feeding to the nut supply hole due to occurrence of nut clogging in the chute when the nut fed in line along the chute is excessively inclined. It is also likely that the nut is not smoothly supplied due to occurrence of nut clogging inside the nut supply hole when the nut is inclined in an occasion of pushing out the nut inside the nut supply hole by the pushrod.